Analysis for protection rate and antibody levels of epidemic cerebrospinal meningitis among children aged between 3-23 months in Liuzhou,in 2012
10.3760/cma.j.issn.0253-9624.2016.12.011
- VernacularTitle:2012年柳州市3~23月龄儿童流行性脑脊髓膜炎抗体水平及保护率分析
- Author:
Xuelian CUI
1
;
Xin WU
;
Mingqiang LI
Author Information
1. 545007柳州市疾病预防控制中心项目办公室
- Keywords:
Neisseria meningitidis,serogroup A;
Neisseria meningitidis,serogroup C;
Serum bacterial assay
- From:
Chinese Journal of Preventive Medicine
2016;50(12):1079-1083
- CountryChina
- Language:Chinese
-
Abstract:
Objective To understand the level of bactericidal antibodies against Neisseria meningitidis and their rate of protection in children aged between 3 and 23 months, in Liuzhou, in 2012. Methods Convenience sampling was performed in Liujiang, Rong'an and Sanjiang Counties from May through August, 2012. The inclusion criteria for 603 subjects were:Children aged between 3 and 23 months;no history of meningococcal meningitis;no vaccination against Neisseria meningitidis serogroup C;more than 30 days from the last vaccination against Neisseria meningitidis serogroup A. Demographic information and immunization history of the subjects were obtained using questionnaires. Venous blood samples (2.0 ml each) were collected and levels of Neisseria meningitides antibodies determined using a Serum Bactericidal Assay (SBA). The geometric mean titer (GMT) of serum bacterial antibodies was positive when it was greater than or equal to 1∶2 and protective when greater than 1∶8. Chi-square and Fisher's exact tests were used to compare differences in the positive and protective rates of serum antibodies of Neisseria meningitidis serogroup A and Neisseria meningitidis serogroup C, among children with different demographic characteristics. Kruskal-Wallis H test was used to compare differences in the GMT of serum antibodies of Neisseria meningitidis serogroup A and Neisseria meningitidis serogroup C, among children with different demographic characteristics. Results Of 603 subjects, 325 (53.9%) were female and 278 (46.1%) were male; 276 (45.8%), 143 (23.7%) and 184 (30.5%) subjects were administered, respectively, no treatment, 1 dose vaccine and 2 doses vaccine. The GMT of serum antibodies against group A Neisseria meningitidis was 1∶1.11, the positive rate was 7.6% (46) and the protective rate was 2.0% (12). The GMT of antibodies in children receiving 1 vaccine dose was 1∶1.16 and the protective rate was 3.5% (5), both values higher than those in children receiving 2 vaccine doses (GMT: 1∶1.2, protective rate: 3.5% (5)). However, these differences were not statistically significant (GMT: H=0.64, P=0.728; protective rate: Fisher's exact test, P= 0.080). The GMT of antibodies in children receiving 1 and 2 doses of meningococcal polysaccharide vaccines were 1∶1.12 and 1∶2.30, respectively (≤180 d). The GMT of serum antibodies for group C meningococcal vaccine was 1∶1.18 and its positive and protective rates were 14.6% (88) and 2.2% (13), respectively. Conclusion Children aged between 3 and 23 months are susceptible to Neisseria meningitidis groups A and C. The immune effectiveness of group A meningococcal polysaccharide vaccine is relatively poor in this age group and their antibody levels decreased rapidly.
